The Seattle Seahawks have given cornerback Richard Sherman a couple more reasons to boast about his team being the best in the NFL. Just three days into the league being officially open for business, they've made the best moves, giving them the early jump in a most competitive NFC race.

It didn't take long for the Seahawks to score two of the best players on the market, wide receiver Percy Harvin (trade with the Minnesota Vikings) and defensive end Cliff Avril (free agent). Those moves also filled their biggest offseason needs—a true go-to guy for second-year QB Russell Wilson and a strong pass rusher. The pass rush got even stronger Thursday evening when they agreed on a one-year deal with former Tampa Bay Buccaneers defensive Michael Bennett.

When poking around the Seahawks' roster, it's getting harder to find any real weakness. Sherman is part of a terrific secondary. In their front seven, the productive Avril joins a sturdy line rotation and Defensive Rookie of the Year finalist Bobby Wagner anchors the linebacker corps.

On offense, Seattle needed to pair Wilson with a big playmaker who could better complement Marshawn Lynch and the power running game. Enter Harvin, who's a lot like Wilson in that he makes up for a lack of size (5-11, 184 pounds) with quick feet, versatility and a toughness that makes him hard to bring down in the open field.

Harvin, though, also comes in with an attitude. That was one reason the Vikings dealt him, but swagger is a Seahawks trademark, from Sherman to head coach Pete Carroll.

"There is not a football player that we could find that can compete more and battles more than this guy right here," Carroll said Tuesday in welcoming Harvin to Seattle. "He'll fit in just right with us."

The Seahawks fell a half-game short of the NFC West title to the eventual conference champion San Francisco 49ers, and then lost by two points in the divisional playoffs to the top-seeded Atlanta Falcons after erasing a 20-point deficit. San Francisco has already made a bang this offseason, acquiring wide receiver Anquan Boldin from the Super Bowl champion Baltimore Ravens right after Harvin was dealt to the Seahawks. Atlanta has kept several of its key players, including Tony Gonzalez, and on Thursday added running back Steven Jackson.

Seahawks general manager John Schneider needed to put up his dukes to help improve Carroll's roster. Landing Harvin and Avril is a great start. The Seahawks gave up a 2013 first-round pick for Harvin, but considering they stole Wagner (second round) and Wilson (third round) later in the draft last year, you can bet Schneider and Carroll will mine a few more gems this year. And unlike the 49ers (safety Dashon Goldson), they haven't lost a key player.

Other teams who have made notable good moves:

Denver Broncos. Former Patriots wide receiver Wes Welker is the biggest name. He should pay huge dividends as Peyton Manning's slot receiver in an already dangerous, versatile passing game. Guard Louis Vasquez, who came at a higher price, fills a huge need along the interior of the offensive line. They strengthened their defensive line with tackle Terrance Knighton, and cornerback Dominique Rodgers-Cromartie could potentially be a huge steal.

Kansas City Chiefs. After finishing 2-14, they need to do a lot to get closer to Denver, and new coach Andy Reid and general manager John Dorsey have been busy overhauling the roster. The headliner is quarterback Alex Smith (trade with the 49ers). They also brought in needed extra weapons for the passing game to help wide receiver Dwayne Bowe and tight end Tony Moeaki: wide receiver Donnie Avery and tight end Anthony Fasano. Also, don’t overlook the fact that they padded a talented defense with tackle Mike DeVito and cornerbacks Sean Smith and Dunta Robinson. Those three are now playing with Derrick Johnson, Tamba Hali, Eric Berry and Brandon Flowers, and Kansas City is looking at Utah lineman Star Lotulelei with the first overall pick in April’s draft.

Miami Dolphins. They of course should have high hopes for the best available free agent, former Steelers wide receiver Mike Wallace, but linebackers Dannell Ellerbe and Phillip Wheeler feel like even better prizes. The Dolphins were wise in not trying to overspend to keep Reggie Bush or Jake Long. Two other players they're chasing—wide receiver Brandon Gibson and tight end Dustin Keller—would make a very good class even better.

Philadelphia Eagles. The Eagles, two years removed from the "Dream Team" defensive strategy that didn't quite work with Nnamdi Asomugha and Rodgers-Cromartie, have quietly rebuilt their defense as they transition to a possible 3-4 alignment under new head coach Chip Kelly and coordinator Billy Davis. They got an entire starting secondary (Cary Williams, Bradley Fletcher, Patrick Chung, Kenny Phillips), and former 49ers nose tackle Isaac Sopoaga, a must for the scheme. They also landed former Houston Texans outside linebacker Connor Barwin, who could return to form as a prolific edge rusher. Another ex-Texan, tight end/fullback/wide receiver/running back James Casey, is a fun new offensive toy for Kelly.

Teams that have made not-so-good moves:

Cleveland Browns. Desperate to catch the Ravens, Cincinnati Bengals and Pittsburgh Steelers in the AFC North, Cleveland threw a lot of money at outside linebacker Paul Kruger and tackle Desmond Bryant to strengthen the defense. Both players come with concerns, however. Can Kruger be the same player away from Baltimore without Terrell Suggs on the other side? Can Bryant reach his massive potential away from a good Oakland Raiders line that included Richard Seymour?

Chicago Bears. They needed a left tackle and a tight end, and they filled those needs with Jermon Bushrod (Saints) and Martellus Bennett (Giants), respectively. But Bushrod's two Pro Bowl trips with New Orleans may have been more a product of playing with Drew Brees and four other great linemen, things he won't have in Chicago. As for Bennett, he was a disappointment with the Dallas Cowboys before flashing ability in New York last season. A player such as Oakland's Brandon Myers could have come a lot cheaper.

St. Louis Rams. St. Louis let its most reliable offensive producer, Jackson, go because of age. It better get a feature option in the draft, because neither Daryl Richardson nor Isaiah Pead can be expected to be workhorses in their second seasons. Jared Cook fills their need for a receiving tight end to help Sam Bradford, but he will need to do a lot more than he did in Tennessee to be worth his new deal. If they do sign Jake Long, the move will look good on paper, but there's a reason Miami didn't want to take the injury risk with him.

Indianapolis Colts. They’ve definitely been high-volume buyers. Gosder Cherilus and Donald Thomas were added to their offensive line. Safety LaRon Landry, versatile lineman Ricky Jean-Francois and cornerback Greg Toler are all projected defensive starters for Chuck Pagano's 3-4. Indy has done considerable spending but has lacked an overall bang for its bucks considering it was a playoff team last season. General manager Ryan Grigson knew what he was doing last year, when he earned Sporting News' NFL Executive of the Year award; if all those new pieces fit together next season, he'll again prove to be smarter than the rest of us.